The Trefftz finite elements modelling crack propagation

  • Henryk Sanecki Cracow University of Technology
  • Andrzej P. Zieliński Cracow University of Technology

Abstract

Investigation of crack propagation can sometimes be a crucial stage of engineering analysis. The T–element method presented in this work is a convenient tool to deal with it. In general, T-elements are the Trefftz-type finite elements, which can model both continuous material and local cracks or inclusions. The authors propose a special T-element in a form of a pentagon with shape functions analytically modelling the vicinity of the crack tip. This relatively large finite element can be surrounded by even larger standard T-elements. This enables easy modification of the rough element grid while investigating the crack propagation. Numerical examples proved that the "moving pentagon" concept enables easy automatic generation of the T-element mesh, which facilitates observation of crack propagation even in very complicated structures with many possible crack initiators occurring for example in material fatigue phenomena.

Keywords

References

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Published
Jul 21, 2022
How to Cite
SANECKI, Henryk; ZIELIŃSKI, Andrzej P.. The Trefftz finite elements modelling crack propagation. Computer Assisted Methods in Engineering and Science, [S.l.], v. 15, n. 3-4, p. 353-368, july 2022. ISSN 2956-5839. Available at: <https://cames.ippt.pan.pl/index.php/cames/article/view/742>. Date accessed: 14 nov. 2024.
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Articles